Washing machine with pressure venting unit

ABSTRACT

Disclosed herein is a venting unit of a washing machine. The washing machine comprises a cabinet having a door mounted thereon, a water tub installed inside the cabinet, a washing tub installed inside the water tub; and a venting unit installed such that an outside of the cabinet is in communication with an inner space of the washing tub through the venting unit. The washing machine has improved drying efficiency.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application claims priority to Korean patent applicationnumber 10-2007-0034384, filed on Apr. 6, 2007, which is incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a venting unit of a washing machine,and more particularly to a washing machine that comprises a washing tubventing unit capable of improving drying efficiency.

2. Description of the Related Art

FIG. 1 is a sectional side elevation of a conventional washing machine.

Referring to FIG. 1, the conventional washing machine includes a cabinet10 having an opening 12 to which a door 14 is mounted, a water tub 16positioned inside the cabinet 10 to contain wash water, a washing tub 18rotatably positioned inside the water tub 16 to receive laundry, a driveunit 17 mounted to the water tub 16 and connected to the washing drum18, a water supply device 19 connected externally to the water tub 16 tosupply wash water to the water tub 16, and a drainage unit 20 extendingfrom the water tub 16 to an outside of the cabinet 10 to discharge washwater.

In the conventional washing machine, when the washing machine isoperated after laundry is put into the washing tub 18 by opening thedoor 14, wash water is supplied into the water tub 16 and the washingtub 18 through the water supply device 19, and power is applied to thedrive unit 17 to perform a washing operation while rotating the washingtub 18. Then, when the washing operation is completed, the wash water isdischarged outside the cabinet 10 through the drainage unit 20.

When the washing and rinsing operations are completed, with the washwater discharged outside the cabinet, power is applied to the drive unit17 to perform a spin drying operation.

When the spin drying operation is started, water contained in thelaundry is expelled to the water tub 16 through a plurality of holes(not shown) formed in the washing tub 18 by a centrifugal force of thewashing tub 18 rotating in the cabinet and discharged outside thecabinet 10 through the drainage unit 20.

In this manner, the conventional washing machine discharges the washwater outside the cabinet through a drainage passage constituted by thedrainage unit 20, which includes a drainage tube 22 extending from thewater tub 16 to outside the cabinet 10 and a drainage valve 24positioned in the drainage tube 20. However, since the conventionalwashing machine is not formed with an air-suction passage, the innerpressure of the water tub 16 and the washing tub 18 decreases during thespin drying operation with the washing tub rotating at high speed, andthus the pressure of air discharged through the drainage unit 20 cannotbe increased above a predetermined value or greater, thereby causing alow drying efficiency.

SUMMARY OF THE INVENTION

The present invention has been made to solve the above problems, and anaspect of the present invention is to provide a washing machine that canimprove drying efficiency.

In accordance with one aspect of the present invention, there isprovided a washing machine comprising: a cabinet having a door mountedthereon; a water tub installed inside the cabinet; a washing tubinstalled inside the water tub; and a venting unit installed such thatan exterior of the cabinet communicates with an inner space of thewashing tub through the venting unit.

The venting unit may be mounted to the door.

The venting unit may comprise a through-hole formed within anair-suction block that is disposed in the cabinet.

The venting unit may further comprise a gate unit mounted on theair-suction block to open or close the through-hole.

The gate unit may comprise a gate member to open or close thethrough-hole, a driving section to drive the gate member, and acontroller to control the driving section.

The air-suction block may be formed along an edge of the door.

The through-hole may be formed in a bent shape.

One side of the through-hole may be formed toward the inner space of thewashing tub.

The washing machine may further comprise a drainage tube incommunication with the water tub, a drainage valve installed in thedrainage tube to open or close the drainage tube, and a controller tocontrol the drainage valve depending on an operating mode of the washingmachine.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention will bemore clearly understood from the following detailed description taken inconjunction with the accompanying drawings, in which:

FIG. 1 is a sectional side elevation of a conventional washing machine;

FIG. 2 is a sectional side elevation of a washing machine according to afirst embodiment of the present invention;

FIG. 3 is a detailed view of Part A in FIG. 2, illustrating across-section of a venting unit of the washing machine according to thefirst embodiment of the present invention;

FIG. 4 is a plan view of the washing machine according to the firstembodiment of the present invention;

FIG. 5 is a block diagram of a drainage unit of the washing machineaccording to the first embodiment of the present invention;

FIG. 6 is a cross-sectional view of a venting unit of a washing machineaccording to a second embodiment of the present invention;

FIG. 7 is a block diagram of the venting unit of the washing machineaccording to the second embodiment of the present invention; and

FIG. 8 is a cross-sectional view of a venting unit of a washing machineaccording to a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of the present invention will be described indetail with reference to the accompanying drawings. For convenience ofdescription, a top-door type washing machine will be described by way ofan example. It should be noted that the drawings are not to precisescale and may be exaggerated in thickness of lines or size of componentsfor descriptive convenience and clarity only. Furthermore, terms usedherein are defined by taking functions of the present invention intoaccount and can be changed according to the custom or intention of usersor operators. Therefore, definition of such terms should be madeaccording to overall disclosures set forth herein.

Referring to FIGS. 2 to 5, the washing machine according to the firstembodiment comprises a cabinet 50 having an opening 52 to which a door54 is mounted, a water tub 62 positioned inside the cabinet 50 tocontain wash water, a washing tub 64 rotatably positioned inside thewater tub 62 to receive laundry, a drive unit 66 to drive the water tub64, a water supply device 68 connected externally to the water tub 62 tosupply wash water, a drainage unit 70 extending from the water tub 62 toan outside of the cabinet 50, and a venting unit 80 installed such thatthe outside of the cabinet communicates with an inner space of thewashing tub 64 through the venting unit 80.

When the washing machine is operated after laundry is put into thewashing tub by opening the door 54, wash water is supplied into thewater tub 62 through the water supply device 68 and power is applied tothe drive unit 66 to perform a washing operation while rotating thewashing tub 64. Then, when the washing and rinsing operations arecompleted, the drive unit 66 is rotated at high speed to perform a spindrying operation.

During the spin drying operation, air is drawn into the water tub 62 andthe washing tub 64 from the outside through the venting unit 80, toprevent a reduction in the inner pressure of the water tub 62 due todischarge of water from the washing tub 64 and water tub 62 to theoutside.

Further, the drainage unit 70 comprises a drainage tube 72 communicatingwith the water tub 62 and a drainage valve 74 positioned in the drainagetube 72 to open or close the drainage tube 72. Operation of the drainagevalve 74 is controlled by a controller 100 described below.

When the spin drying operation is started, the drive unit 66 is rotatedat high speed, and, when it is rotated at a predetermined speed orgreater, the controller 100 opens the drainage valve 74 in response tosuch rotation of the drive unit 66. When the drainage valve 74 isopened, air drawn into the water tub 62 and the washing tub 64 via athrough-hole 82 makes contact with laundry and is then dischargedtogether with moisture contained in the air to outside the cabinet 50through the drainage tube 72. Here, the controller 100 controls therotational speed and rotational force of the drive unit 66 depending onwashing mode. Since such a method of detecting the mode of the washingoperation is generally adopted by typical washing machines, detaileddescription thereof will be omitted herein.

The venting unit 80 is installed to the door 54 such that air can bedrawn towards an upper surface of the washing tub 64. The venting unit80 comprises an air-suction block 84 in which is formed a through-hole82. Air is drawn through the through-hole 82 from the outside into thewashing machine to the inner space of the washing tub 64. Preferably,the through-hole 82 is formed in a bent shape such that, when drawn intothe through-hole 82, air can flow into the water tub 62 and the washingtub 64, but foreign matter can be collected at an inner wall of thethrough-hole 82 while flowing through the through-hole 82. On the otherhand, during rotation of the washing tub 64, air inside the washing tub64 moves towards the water tub 62. Such a movement of air lowerspressure in the washing tub 64, that is, the pressure at the center ofthe washing tub 64. Therefore, it is preferable that one end 92 of thethrough-hole 82 is formed to open toward the inner space of the washingtub 64 to obtain smooth circulation of air within the washing machine.

In this embodiment, the through-hole 82 extends from an upper surface ofthe air-suction block 84 in a downward direction, is bent primarily,extends a predetermined distance in a lateral direction, and is bentsecondarily in the downward direction. When drawn into the through-hole82 through the upper surface of the air-suction block 84, foreign matterpasses through the primarily bent section 86 of the through-hole 82 andbecomes accumulated in a laterally extending section 90 of thethrough-hole 82, the laterally extending section 90 residing between theprimarily bent section 86 and the secondarily bent section 88.

The air-suction block 84, having the through-hole 82 formed therein, ismounted to the door 54 or the cabinet 50. Preferably, to improve theappearance of the washing machine, the air-suction block 84 is disposedcorresponding to the shape of the door 54. In this embodiment, theair-suction block 82 is disposed in a curved shape along a circular edgeof the door 52. In addition, although the air-suction block 84 isprovided as a separate member from the door 54 or the cabinet 50 in thisembodiment, various modifications of the air-suction block can be made,for example, by integrating a function of the air-suction block withinthe door 54 or the cabinet 50.

For installation of such an air-suction block 84, a portion of thecircumference of the opening 52 is formed with a step 56 on which theair-suction block 84 is seated. Since the step 56 is provided to seatthe air-suction block 84 thereon, a lower end 92 of the through-hole 82is disposed in a space between the door 54 and the step 56. Thisconfiguration prevents interference between the lower end 92 of thethrough-hole 82 and the step 56, so that the lower end 92 of thethrough-hole 82 can face the interior of the washing tub 64.

Operation of the washing machine according to the first embodimenthaving such a construction as described above will be described asfollows.

First, when the washing machine is operated after laundry is put intothe washing tub 64 by opening the door 54, wash water is supplied intothe washing tub 64 and the water tub 62 through the water supply device68, and after finishing water supply, power is applied to the drive unit66 to perform a washing operation with wash water rotated in the washingtub 18.

If desired, washing and rinsing operations are repeated several times,and then the wash water is discharged to the outside through thedrainage unit 70 and the drive unit 66 is rotated at high speed toperform a spin drying operation. Such a series of operations iscontrolled by the controller 100.

When the spin drying operation is started, rotation speed of the driveunit 66 is detected by the controller 100. Here, if the rotation speedof the drive unit 66 reaches a preset value or greater, the controller100 opens the drainage valve 74 based on the judgment that the washingmachine is performing the spin drying operation. Then, air is drawn fromthe exterior into the water tub 62 and the washing tub 64 through thethrough-hole 82, and contacts the laundry to absorb moisture from it. Inthis manner, the spin drying operation is performed while air, includingabsorbed moisture therein, is discharged outside the cabinet 50 throughthe drainage tube 72. At this time, since air is drawn from the exteriorinto the water tub 62 through the through-hole 82, it is possible toprevent reduction in a discharge rate of air due to pressure decreasewithin the water tub 62 by discharge of the air through the drainagetube 72.

With such a construction and operation as described above, the washingmachine of the present invention has improved drying efficiency. Toprove such an effect of the present invention, inventors of the presentinvention carried out a test to compare the drying rates of an inventivewashing machine according to the first embodiment compared with those ofa conventional washing machine.

For the test, the inventors employed washing machines, of whichspecifications are shown in Table 1.

TABLE 1 Rated Voltage AC 100 V, 50/60 Hz Washing Capacity/DryingCapacity 5.5 Kg/1.5 Kg Power Consumption 280 W/330 W Water quantity 130l Dimensions 563 * 550 * 948 mm Feature Drying operation by induction ofexternal air without heater

Table 2 shows various drying rates of an inventive washing machineaccording to the first embodiment compared with those of a conventionalwashing machine.

The drying ratios shown in Table 2 were obtained by spin drying testclothes using the conventional washing machine and the inventive washingmachine. Here, standard clothes, cotton trousers, a dress shirt, and thegroup consisting of cotton trousers, a dress shirt, a cotton tee shirt,underclothes, and socks were adopted as the test clothes.

Further, the respective test clothes put into each of the washingmachines weighed 1.5 kg and were dried for 30 minutes through spindrying operation of the washing machines. In each test, the spin dryingoperation was repeated five times to obtain drying rates of therespective test samples, average values of which are shown in Table 2.

As can be seen from Table 2, the washing machine of the presentinvention having the through-hole 82 formed therein has a noticeablyimproved drying rate.

TABLE 2 Test Clothes Cotton trousers + Dress shirt + Cotton StandardCotton Dress tee shirt + Clothes Trousers shirt Underclothes + SocksConventional 52.53 65.12 71.68 61.66 Washing Machine Inventive 60.175.22 77.73 69.45 Washing Machine Improved rate 7.57 10.1 6.05 7.79

FIG. 6 is a cross-sectional view of a venting unit of a washing machineaccording to a second embodiment of the present invention, and FIG. 7 isa block diagram of the venting unit of the washing machine according tothe second embodiment of the present invention.

Referring to FIGS. 6 and 7, the washing machine according to the secondembodiment comprises a modified venting unit. The venting unit 180 ofthe washing machine according to the second embodiment comprises athrough-hole 182, an air-suction block 184 having the through-hole 182formed therein, and a gate unit 90 to open and close the through-hole182.

Here, the gate unit 90 comprises a gate member 92 to open and close thethrough-hole 182, and a driving section 94 to drive the gate member 92.The controller 100 is used to control the driving section 94.

When the controller 100 detects a spin drying operation of the washingmachine in response to variation in rotation speed of the drive unit 66,the driving section 94 moves the gate member 92 to open the through-hole182.

Additionally, when detecting the spin drying operation of the washingmachine, the controller 100 sends an open signal to the drainage valve74 of the washing machine to open the drainage valve 74. Air is drawninto the washing tub 64 through the through-hole 182 and absorbsmoisture from laundry in the washing tub 64, and is then dischargedoutside the cabinet 50 through the drainage tube 72.

In this embodiment, the gate member 92 is constituted by a panel woundaround a gear wheel, and opens or closes the through-hole 182 dependingon operation of the driving section 94. In other words, when a powertransmission member such as the gear wheel is rotated by the drivingsection 94, the gate member 92 opens or closes the through-hole 182 inresponse to the rotation of the power transmission member.

FIG. 8 is a cross-sectional view of a venting unit of the washingmachine according to a third embodiment of the present invention.

Referring to FIG. 8, it can be seen that the third embodiment is similarto the second embodiment in that a gate unit 190 is provided to open andclose a through-hole 282. However, the venting unit 280 of the washingmachine according to the third embodiment does not include a drive unitfor opening and closing a gate member 192, but instead provides a gatemember 192 that is opened or closed manually.

The gate member 192 is constituted by a panel installed such that it canbe slidably moved inward and outward through a through-hole 282. Forthis purpose, an air-suction block 284 is formed with a guide 194 suchthat the gate member 192 can slide stably along the guide 194 between afirst position obstructing the through hole 282 and a second position inwhich it is received within the air-suction block 284 leaving thethrough hole 282 substantially unobstructed.

As apparent from the above description, the washing machine according tothe present invention comprises a venting unit through which air issupplied from outside into a water tub and a washing tub in order toprevent a reduction in the pressure of the washing tub due to airdischarge through a drainage tube during drying operation, therebyensuring efficient air circulation and improvement of drying efficiency.Furthermore, unlike the conventional washing machine, the washingmachine according to the present invention can improve the dryingefficiency without a separate drying device such as a heater. Moreover,since it is possible to improve the drying efficiency without theseparate drying device such as the heater, the washing machine accordingto the present invention has a simple construction with a reduced numberof components and thus a lower price.

Although the present invention has been described with reference to theembodiments shown in the drawings, it should be understood that theseembodiments are provided for illustrative purposes and that variousequivalent modifications and alterations will be apparent to thoseskilled in the art without departing from the scope and spirit of thisinvention. In addition, although the present invention has beendescribed with reference to the washing machine having the venting unitfor drying as specifically described herein, it should be noted that thewashing machine having the venting unit has been illustrated as anexample, and that such a venting unit for drying of the presentinvention may be applied to other dryers without being limited to adryer for a washing machine. Therefore, the scope and spirit of theinvention is limited only by the claims set forth herein as follows.

1. A washing machine, comprising: a cabinet having a door mountedthereon; a water tub installed inside the cabinet; a washing tubinstalled inside the water tub; and a venting unit installed such thatan exterior of the cabinet communicates with an inner space of thewashing tub through the venting unit.
 2. The washing machine accordingto claim 1, wherein the venting unit is mounted to the door.
 3. Thewashing machine according to claim 1, wherein the venting unit comprisesan air suction block, and wherein a through-hole is formed in theair-suction block through which the exterior of the cabinet communicateswith the inner space of the washing tub.
 4. The washing machineaccording to claim 3, wherein the venting unit further comprises a gateunit configured to selectively open and close the through-hole.
 5. Thewashing machine according to claim 4, wherein the gate unit comprises agate member movable between a first position in which the through-holeis open and a second position in which the through-hole is closed, adriving section which drives the movement of the gate member, and acontroller which controls the driving section.
 6. The washing machineaccording to claim 3, wherein the air-suction block is formed in thecabinet.
 7. The washing machine according to claim 6, wherein theair-suction block is formed along an edge of the door.
 8. The washingmachine according to claim 3, wherein the air-suction block is formedsuch that the through-hole is formed in a bent shape.
 9. The washingmachine according to claim 8, wherein one end of the through-hole isformed to open toward the inner space of the washing tub.
 10. Thewashing machine according to claim 1, further comprising: a drainagetube in communication with the water tub; a drainage valve disposed inthe drainage tube, the drainage valve configured to selectively open andclose the drainage tube; and a controller which controls the drainagevalve depending on an operating mode of the washing machine.
 11. Thewashing machine according to claim 5, further comprising: a drainagetube in communication with the water tub; a drainage valve disposed inthe drainage tube, the drainage valve configured to selectively open andclose the drainage tube; wherein the controller controls the drivingsection and drainage valve depending on an operating mode of the washingmachine.